via Improbable research: The Van Der Waals brakeeps strapless bras up by using the same idea as geckos use to climb walls
so what is the VanDerWaals force?the weak attraction between certain molecules.
The ability of geckos – which can hang on a glass surface using only one toe – to climb on sheer surfaces has been attributed to the van der Waals forces between these surfaces and the spatulae, or microscopic projections, which cover the hair-likesetae found on their footpads. A later study suggested that capillary adhesion might play a role, but that hypothesis has been rejected by more recent studies. There were efforts in 2008 to create a dry glue that exploits the effect,and success was achieved in 2011 to create an adhesive tape on similar grounds. In 2011, a paper was published relating the effect to both velcro-like hairs and the presence of lipids in gecko footprints.